What do angels and cabbages have in common?
Well, they both share the Hebrew word kruv כרוב, but except for Jastrow - who provides the unconvincing shared etymology "round" - no one says they share a common root.
For kruv as the Biblical word meaning "angel" - recognized clearly in the English word "cherub" - Klein provides the following etymology:
Klein also writes that the words griffin and gryphon may be related:
Related to Akkadian karabu (= to bless), karibu ( = one who blesses), epithet of the bull-colossus, and to ברך (= to bless)
[Klein] suggests a Sem. source, "through the medium of the Hittites," and cites Heb. kerubh "a winged angel," Akkad. karibu, epithet of the bull-colossusThe Jewish Encyclopedia provides some additional theories:
Following Lenormant's suggestions, Friedrich Delitzsch connected the Hebrew with the Assyrian "kirubu" = "shedu" (the name of the winged bull). Against this combination see Feuchtwang, in "Zeitschrift für Assyriologie," etc., i. 68 et seq.; Teloni, ib. vi. 124 et seq.; Budge, in "The Expositor," April and May, 1885. Later on, Delitzsch ("Assyrisches Handwörterbuch," p. 352) connected it with the Assyrian "karubu" (great, mighty); so, also, Karppe, in "Journal Asiatique," July-Aug., 1897, pp. 91-93. Haupt, in Toy, "Ezekiel" ("S. B. O. T."), Hebrew text, p. 56, line 11, says: "The name may be Babylonian; it does not mean 'powerful,' however, but 'propitious' (synonym 'damḳu')." For the original conception of the Babylonian cherubim see Haupt's notes on the English translation of Ezekiel, pp. 181-184 ("S. B. O. T."), and the abstract of Haupt's paper on "Cherubim and Seraphim," in the "Bulletins of the Twelfth International Congress of Orientalists," No. 18, p. 9, Rome, 1899. See also Haupt, in Paterson, "Numbers" ("S. B. O. T."), p. 46: "The stem of is the Assyrian 'karâbu' (= be propitious, bless), which is nothing but a transposition of the Hebrew .ברך" Dillmann, Duff, and others still favor the connection with γρύψ ("gryphus" = the Hindu "Garuda.")
Kruv meaning cabbage entered Hebrew in Talmudic times. Ben-Yehuda introduced the related kruvit כרובית - cauliflower. As to the etymology of kruv (cabbage), Klein writes:
Together with Aramaic כרובא, כרבא, Syrian כרבא, borrowed from Greek krambe, which is related to krambos ( = dry shriveling), kromboyn (= to roast), and cognate with Old German hrimfan, rimfan ( = to contract, wrinkle), Old English hrympel (= wrinkle)The English word "rumple" derives from hrympel.
From the Greek word krambe, we get the following expression: "dis krambe thanatos" meaning:
Cabbage, twice over, is death; repetition is tedious
Latin (in which crambe also means cabbage) has a similar phrase: "Crambe bis Cocta", meaning "cabbage boiled twice" - a subject hacked out.
These expressions led to the name of a game - "crambo" which is:
a word game in which one team says a rhyme or rhyming line for a word or line given by the other team
While I can't find any Biblical or Talmudic texts where it is unclear whether kruv refers to an angel or a cabbage, I did find one modern example. On the Hebrew version of Sesame Street, Rechov Sumsum, the Hebrew name for the Grover character is "Kruvi". The Muppet Wiki discusses the etymology:
Kruvi (most likely "small cabbage", although possibly "little angel", "cherub")
I never really thought about it before, but Grover's head is kind of cabbage shaped...